The balloting that began at 8am will continue till 4pm without any break.
In the 117 upazilas, some 340 chairman, 584 vice-chairman and 399 woman vice-chairman candidates are contesting the elections.
Besides, 33 chairman, nine vice-chairman and 13 woman vice-chairman contestants have already been elected uncontested in the absence of any valid candidate to oppose them.
In Chattogram, a police constable and a man sustained bullet injuries as miscreants attacked and opened fire at a polling station in Chandnaish upazila around 9:30am.
Following the incident, the election commission has suspended voting in the centre.
In Cox’s Bazar, at least four people sustained bullets in a clash near a polling centre in Mognama union of Pekua upazila in the morning.
In Kishoreganj, the Election Commission has suspended voting at all centres of Katiadi upazila following allegations of huge irregularities.
Besides, additional superintendent of police Shafiqul Islam and Katiadi Police Station Officer-in-charge Shamsuddin have been withdrawn over the incidents of vote rigging, said district election officer Mohammad Tajul Islam.
The first phase and second phase elections were held on March 10 and 18 respectively, while the fourth phase polls are scheduled to be held on March 31.
The first upazila election was held in 1985, while the following three were held in 1990, 2009 and 2014.